U.S. patent number 6,782,672 [Application Number 10/266,224] was granted by the patent office on 2004-08-31 for sandwich panel structural joint.
This patent grant is currently assigned to Alliance Spacesystems, Inc.. Invention is credited to James R. Staats.
United States Patent |
6,782,672 |
Staats |
August 31, 2004 |
Sandwich panel structural joint
Abstract
A sandwich panel structure comprises a slotted panel and a
tabbed panel. The slotted panel includes a slotted panel core body
and a first slotted panel facesheet. The slotted panel core body
defines a first slotted panel side with the first slotted panel
facesheet disposed adjacent thereto and including a plurality of
first slots. The tabbed panel includes a tabbed panel core body and
a first tabbed panel facesheet, the tabbed panel core body defining
a first tabbed panel side with the first tabbed panel facesheet
disposed thereto. The first tabbed panel facesheet includes a
plurality of first tabs disposed along a first joint edge with each
of the first tabs respectively sized and configured to be received
by a respective one of the first slots upon insertion of the first
tabs into the first slots for joining the tabbed panel to the
slotted panel at the first joint edge.
Inventors: |
Staats; James R. (Santa
Clarita, CA) |
Assignee: |
Alliance Spacesystems, Inc.
(Pasadena, CA)
|
Family
ID: |
32042626 |
Appl.
No.: |
10/266,224 |
Filed: |
October 8, 2002 |
Current U.S.
Class: |
52/591.2; 52/272;
52/588.1; 52/589.1 |
Current CPC
Class: |
B32B
3/02 (20130101); E04C 2/365 (20130101); B32B
15/043 (20130101); B32B 3/12 (20130101); B32B
2607/00 (20130101) |
Current International
Class: |
B32B
3/02 (20060101); E04C 2/36 (20060101); E04C
2/34 (20060101); E04B 001/38 () |
Field of
Search: |
;52/272,284,791.1,793.1,309.9,588.1,591.2,592.1,36.5,36.6,589.1
;446/124 ;428/116,192 ;244/131 ;403/231,375,381 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Canfield; Robert
Attorney, Agent or Firm: Stetina Brunda Garred &
Brucker
Claims
What is claimed is:
1. A sandwich panel structure comprising: a slotted panel including
a slotted panel core body and a first slotted panel facesheet, the
slotted panel core body defining opposing first and second slotted
panel sides, the first slotted panel facesheet disposed adjacent
the first slotted panel side and including a plurality of first
slots formed therethrough; and a tabbed panel including a tabbed
panel core body and a first tabbed panel facesheet, the tabbed
panel core body defining opposing first and second tabbed panel
sides, the first tabbed panel facesheet disposed adjacent the first
tabbed panel side, the first tabbed panel facesheet including a
first joint edge and a plurality of first tabs disposed along the
first joint edge with each of the first tabs respectively sized and
configured to be received by a respective one of the first slots
upon insertion of the first tabs into the first slots for joining
the tabbed panel to the slotted panel at the first joint edge, the
first tabs extending through at least about 50 percent of a
thickness of the slotted panel core body.
2. The sandwich panel structure of claim 1 wherein the first tabs
are bonded to the first slots.
3. The sandwich panel structure of claim 1 wherein the tabbed panel
is disposed generally perpendicular to the slotted panel.
4. The sandwich panel structure of claim 1 wherein the tabbed panel
is disposed at an angle from about 45.degree. to about 135.degree.
to the slotted panel.
5. The sandwich panel structure of claim 1 wherein the first tabs
are aligned.
6. The sandwich panel structure of claim 1 wherein the first tabs
extend through at least about 80 percent of a thickness of the
slotted panel core body.
7. The sandwich panel structure of claim 1 wherein the slotted
panel includes a second slotted panel facesheet disposed adjacent
the first slotted panel side.
8. The sandwich panel structure of claim 7 wherein the tabbed panel
includes a second tabbed panel facesheet disposed adjacent the
second tabbed panel side.
9. The sandwich panel structure of claim 1 wherein the first tabbed
panel facesheet is constructed of a heat conducting material.
10. The sandwich panel structure of claim 1 wherein the first
slotted panel facesheet is formed of a metal material.
11. The sandwich panel structure of claim 1 wherein the first
tabbed panel facesheet is formed of a metal material.
12. The sandwich panel structure of claim 1 wherein the tabbed
panel core body is formed of a cellular material.
13. The sandwich panel structure of clam 12 wherein the cellular
material is a honeycomb material.
14. The sandwich panel structure of claim 13 wherein the honeycomb
material includes a plurality of cells, the cells define
longitudinal axes extending perpendicular to the first and second
slotted panel, the first tabs extend through the first slots
parallel to the longitudinal axes of the cells.
15. The sandwich panel structure of claim 14 wherein the
orientation of the longitudinal axes of the cells parallel to the
first tabs aids in the conduction of heat from the first tabbed
panel facesheet to the second slotted panel side.
16. The sandwich panel structure of claim 1 wherein the tabbed
panel core body and the slotted panel core body are formed of a
metal material.
17. The sandwich panel structure of claim 1 wherein the slotted
panel core body defines a slotted panel end, the first slots are
disposed adjacent to and along the slotted panel end, the tabbed
panel core body further includes a second tabbed panel facesheet
disposed adjacent the slotted panel end with the first tabs
received by the first slots.
18. The sandwich panel structure of claim 1 wherein the first
slotted panel facesheet further includes a plurality of first and
second slots, the first and second slots are formed through the
first slotted panel facesheet and are arranged in two generally
parallel rows, the tabbed panel further includes a second tabbed
panel facesheet, the second tabbed panel facesheet is disposed
adjacent the second tabbed panel side, the second tabbed panel
facesheet further includes a plurality of second tabs disposed
respectively along a second joint edge, each of the second tabs is
respectively sized and configured to be received by a respective
one of the first and second slots upon insertion of the second tabs
into the respective second slots for joining the tabbed panel to
the slotted panel at the second joint edge.
19. A sandwich panel structure comprising: a slotted panel
including a slotted panel core body and a first slotted panel
facesheet, the slotted panel core body defining opposing first and
second slotted panel sides, the first slotted panel facesheet
disposed adjacent the first slotted panel side and including a
plurality of first slots formed therethrough; and a tabbed panel
including a tabbed panel core body and a first tabbed panel
facesheet, the tabbed panel core body defining opposing first and
second tabbed panel sides, the first tabbed panel facesheet
disposed adjacent the first tabbed panel side, the first tabbed
panel facesheet including a first joint edge and a plurality of
first tabs disposed along the first joint edge with each of the
first tabs respectively sized and configured to be received by a
respective one of the first slots upon insertion of the first tabs
into the first slots for joining the tabbed panel to the slotted
panel at the first joint edge, the tabbed panel core body being
formed of a cellular honeycomb material, the honeycomb material
including a plurality of cells, the cells defining longitudinal
axes extending perpendicular to the first and second slotted panel,
the first tabs extending through the first slots parallel to the
longitudinal axes of the cells.
20. A sandwich panel structure comprising: a slotted panel
including a slotted panel core body and a first slotted panel
facesheet, the slotted panel core body formed of a metal material
and defining opposing first and second slotted panel sides, the
first slotted panel facesheet disposed adjacent the first slotted
panel side and including a plurality of first slots formed
therethrough; and a tabbed panel including a tabbed panel core body
and a first tabbed panel facesheet, the tabbed panel core body
formed of a metal material and defining opposing first and second
tabbed panel sides, the first tabbed panel facesheet disposed
adjacent the first tabbed panel side, the first tabbed panel
facesheet including a first joint edge and a plurality of first
tabs disposed along the first joint edge with each of the first
tabs respectively sized and configured to be received by a
respective one of the first slots upon insertion of the first tabs
into the first slots for joining the tabbed panel to the slotted
panel at the first joint edge.
21. A sandwich panel structure comprising: a slotted panel
including a slotted panel core body and a first slotted panel
facesheet, the slotted panel core body defining opposing first and
second slotted panel sides, the first slotted panel facesheet
disposed adjacent the first slotted panel side, the first slotted
panel facesheet including a plurality of first and second slots
formed therethrough arranged in two generally parallel rows; and a
tabbed panel including a tabbed panel core body, a first tabbed
panel facesheet and a second tabbed panel facesheet, the tabbed
panel core body defining opposing first and second tabbed panel
sides, the first tabbed panel facesheet disposed adjacent the first
tabbed panel side, the second tabbed panel facesheet disposed
adjacent the second tabbed panel side, the first tabbed panel
facesheet including a first joint edge and a plurality of first
tabs disposed along the first joint edge with each of the first
tabs respectively sized and configured to be received by a
respective one of the first slots upon insertion of the first tabs
into the first slots for joining the tabbed panel to the slotted
panel at the first joint edge, the second tabbed panel facesheet
including a plurality of second tabs disposed respectively along a
second joint edge, each of the second tabs being respectively sized
and configured to be received by a respective one of the first and
second slots upon insertion of the second tabs into the respective
second slots for joining the tabbed panel to the slotted panel at
the second joint edge.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
(Not Applicable)
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
(Not Applicable)
BACKGROUND OF THE INVENTION
The present invention relates generally to sandwich panels and,
more particularly, to a sandwich panel structural joint.
Sandwich panels are increasingly used in aerospace products such as
aircraft, helicopters, and spacecraft due to their desirable
strength, weight, and stiffness characteristics. Sandwich panels
are typically comprised of a panel core body having opposing first
and second panel sides with at least one panel facesheet attached
to the panel core body adjacent the first panel side. In this
regard, a sandwich panel is a layered construction formed by
bonding at least one or, more typically, two thin panel facesheets
to the thicker panel core body. A sandwich panel is of a stressed
skin type of construction in which the facesheets resist all, or
nearly all, of the applied edgewise loads and planar bending
moments. The spacing between the thin facesheets provides all, or
nearly all, of the bending rigidity to the sandwich panel
construction. The core body spaces the facesheets and transmits
shear loads between them so that they are effective about a neutral
axis. The core body also provides most of the shear rigidity of the
sandwich panel construction. Proper choice of materials for the
facesheets and the core body results in a sandwich panel
construction with a high ratio of stiffness to weight. Sandwich
panels must be joined to provide stiff frames capable of handling
the high stresses typical of aerospace fight vehicles. The sandwich
panel joints must be capable of handling bending moment, shear,
tension and compression stresses.
In addition, the sandwich panel joints in spacecraft can also serve
a secondary purpose in aiding in the dissipation of excess heat
generated by instrumentation mounted in the interior of the
spacecraft. As an aid to the active cooling system common to many
spacecraft, heat can be conducted to the spacecraft exterior from
the sandwich panels upon which the instrumentation and electronics
are mounted. However, sandwich panels do not readily conduct heat
across the core body to the exterior because the core body is
generally constructed of a cellular material. Therefore, it is
highly desirable to have a sandwich panel joint configuration that
can assist in the conduction of heat from the interior facesheet
upon which instrumentation is mounted to an exterior facesheet of
an adjacent panel.
Prior art approaches for sandwich panel joint configurations are
numerous. For example, the prior art describes a sandwich panel
structural member which includes an integrally formed joint-forming
edge structure. The joint-forming edge structure is adapted to be
bonded to a complementary integrally formed joint-forming edge
structure, such that the joining of any two sandwich panel
structural members with the same edge structure requires no
separate joining members to assist in the handling of joint loads.
Each joint-forming edge structure includes a flange that extends
from the sandwich portion of the sandwich panel, a web that extends
from one panel skin to the other, and a flange-receiving portion
integrally formed with and extending inward from the joint edge.
Although this joint configuration has the benefit of accommodating
any panel having the same integral edge configuration, the
drawbacks are that it requires many additional joint structural
members that must be laid up over the entire edge portion of each
panel, necessitating special edge tooling and increasing the
manufacturing cost and complexity.
The prior art also describes a sandwich panel construction
utilizing a single piece of folded thermoplastic-composite-skinned,
honeycomb-cored sandwich panel utilizing minimum edge-margin
mortise and tenon joint corner structure. Formed by folding the
single piece of sandwich panel material into a locking open box
type structure, the sandwich panel structure contains interlocking
joints characterized as mortise and tenon joints. End panels are
folded up from the sides of a bottom panel to form side walls.
Tenons extend from the margins of the right and left end panels.
Mortise packets are formed in the side margins of the upper panels.
The mortises and tenons create interlocking mortise and tenon
joints, requiring no additional joint members. The manufacturing
advantages of this sandwich panel structure are that it is
constructed of one piece and is essentially self-tooling in that it
has interlocking joints requiring no adhesive. However, the
drawback of this configuration is that it is incapable of handling
high loading conditions often encountered in aerospace flight
vehicles.
Also included in the prior art is a composite sandwich panel joint
comprising a first and second article. The first and second
articles each include a filler layer disposed between a first and
second composite layer. An end section of the first article's first
composite layer is disposed external to, overlapping and bonded to
an end section of the second article's first composite layer to
form a first overlap. An end section of the second article's second
composite layer is disposed internal to, overlapping and bonded to
an end section of the first article's second composite layer to
form a second overlap. The first overlap is displaced across the
thickness and along the length of the joint from the second
overlap. Loads are transferred across the joint from first layer to
first layer and from second layer to second layer. Although this
configuration has improved ability to withstand axial and bending
loads, it has drawbacks in that it is complex and has a lengthy
manufacturing time due to the additional joint members that must be
concurrently laid up and co-cured over the entire edge of each
panel.
As can be seen, there is a need for a sandwich panel joint
configuration for a sandwich panel structure that is capable of
providing an efficient load path across adjacent sandwich panel.
Also, there is a need for a sandwich panel joint configuration that
is of simple construction with a minimal number of parts.
Furthermore, there is a need for a sandwich panel joint
configuration with improved heat conduction capabilities across
adjacent composite panels. Finally, there is a need for a simple
sandwich panel joint configuration that easily connects sandwich
panels having substantially differing thicknesses.
BRIEF SUMMARY OF THE INVENTION
The present invention specifically addresses and alleviates the
above referenced deficiencies associated with sandwich panels. More
particularly, the present invention is an improved sandwich panel
joint configuration.
In accordance with an embodiment of the present invention, there is
provided a sandwich panel structure comprising a slotted panel and
a tabbed panel. The slotted panel includes a slotted panel core
body and a first slotted panel facesheet. The slotted panel core
body further defines opposing first and second slotted panel sides.
The first slotted panel facesheet is disposed adjacent the first
slotted panel side and further includes a plurality of first slots
formed therethrough.
The tabbed panel includes a tabbed panel core body and a first
tabbed panel facesheet. The tabbed panel core body further defines
opposing first and second tabbed panel sides, the first tabbed
panel facesheet disposed adjacent the first tabbed panel side. The
first tabbed panel facesheet further includes a first joint edge
and a plurality of first tabs disposed along the first joint edge
with each of the first tabs respectively sized and configured to be
received by a respective one of the first slots upon insertion of
the first tabs into the first slots for joining the tabbed panel to
the slotted panel at the first joint edge.
The sandwich panel structure of the present invention differs from
existing sandwich panel structures in that the sandwich panel joint
configuration of the present invention provides an efficient load
path across adjacent sandwich panels. In addition, the sandwich
panel joint configuration of the present invention may provide
improved heat conduction characteristics across the joint. This is
because a tabbed panel facesheet of an interior panel that supports
instrumentation may also transfer the heat generated by the
instrumentation to the exterior of an adjacent slotted panel.
According to various embodiments, the tabbed panel may be disposed
generally perpendicular to the slotted panel. The tabbed panel may
further be disposed at an angle from about 45.degree. to about
135.degree. to the slotted panel. The first tabs may further be
aligned and in another embodiment, the first tabs may be bonded to
the first slots. The first tabs may extend through at least about
50 percent of a thickness of the slotted panel core body, and in
another embodiment the first tabs may extend through at least about
80 percent of a thickness of the slotted panel core body.
The slotted panel may further include a second slotted panel
facesheet disposed adjacent the first slotted panel side. The
tabbed panel may further include a second tabbed panel facesheet
disposed adjacent the second tabbed panel side. The first tabbed
panel facesheet may further be constructed of a heat conducting
material. The first slotted panel facesheet may be formed of a
metal material. The first tabbed panel facesheet may also be formed
of a metal material.
The tabbed panel core body may further be formed of a cellular
material. The cellular material may further be a honeycomb
material. The honeycomb material may further include a plurality of
cells, the cells further defining longitudinal axes extending
perpendicular to the first and second slotted panel with the first
tabs further extending through the first slots parallel to the
longitudinal axes of the cells. The orientation of the longitudinal
axes of the cells parallel to the first tabs may further aid in the
conduction of heat away from the first tabbed panel facesheet to
the second slotted panel side. The tabbed panel core body and the
slotted panel core body may further be formed of a metal material.
The slotted panel core body may further define a slotted panel end
and the first slots may further be disposed adjacent to and along
the slotted panel end. The tabbed panel core body may further
include a second tabbed panel facesheet disposed adjacent the
slotted panel end with the first tabs received by the first
slots.
The first slotted panel facesheet may further include a plurality
of first and second slots and the first and second slots may
further be formed through the first slotted panel facesheet and
arranged in two generally parallel rows. The tabbed panel may
further include a second tabbed panel facesheet and the second
tabbed panel facesheet may further by disposed adjacent the second
tabbed panel side. The second tabbed panel facesheet may further
include a plurality of second tabs disposed respectively along a
second joint edge. Each of the second tabs may further be
respectively sized and configured to be received by a respective
one of the first and second slots upon insertion of the second tabs
into the respective second slots for joining the tabbed panel to
the slotted panel at the second joint edge.
BRIEF DESCRIPTION OF THE DRAWINGS
These as well as other features of the present invention will
become more apparent upon reference to the drawings wherein:
FIG. 1 is a perspective view of a sandwich panel structure in
accordance with the present invention;
FIG. 2 is an exploded perspective view of the sandwich panel
structure of FIG. 1 illustrating the connective relationship of the
tabbed panels and slotted panels that make up the sandwich panel
structure;
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 1
illustrating the arrangement of the sandwich panel joint
configuration wherein a first tabbed panel facesheet of a tabbed
panel is engaged with a slotted panel;
FIG. 4 is a side view of a portion of the tabbed panel taken along
line 4--4 of FIG. 3 illustrating the arrangement of the tabs along
a joint edge of the tabbed panel;
FIG. 5 is an exploded perspective view of the sandwich panel
structure taken from an interior perspective of FIG. 1 illustrating
the connective relationship of the tabbed panel with the slotted
panel;
FIG. 6 is a cross-sectional view taken along line 6--6 of FIG. 1
illustrating the arrangement of the sandwich panel joint
configuration wherein opposing first and second tabbed panel
facesheets of the tabbed panel are engaged to the first slotted
panel facesheet of the slotted panel; and
FIG. 7 is an exploded perspective view of the sandwich panel
structure taken from an interior perspective of FIG. 1 illustrating
the connective relationship of the opposing tabbed panel facesheets
of the tabbed panel with the slotted panel facesheets of the
slotted panel.
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will now be described in
particular with reference to the accompanying drawings.
Referring to FIG. 1, shown is a sandwich panel structure 10
incorporating the joint configurations of the present invention. In
the embodiment shown, the sandwich panel structure 10 is comprised
of panels 12, 14, 16, 18, 20 and 22 assembled to form a six-sided
box structure. It is recognized herein that there are an infinite
number of panel arrangements that may be assembled to form a
sandwich panel structure utilizing the joint configurations of the
present invention as will be described in more detail below.
Referring now to FIG. 2, shown is an exploded perspective view of
the sandwich panel structure 10 of FIG. 1 illustrating the
connective relationship of tabbed panels 42 and slotted panels 24
that make up the sandwich panel structure 10. In FIG. 2, panel 12
is shown having borders 12a, 12b, 12c and 12d disposed peripherally
thereon. Borders 12a and 12b each include a plurality of first tabs
58 extending therefrom. Panel 14 has borders 14a, 14b, 14c and 14d
disposed peripherally thereon. Border 14a includes a plurality of
first slots 38 for receiving the first tabs 58 of border 12a. Panel
16 includes borders 16a, 16b, 16c and 16d disposed peripherally
thereon, with border 16b including first slots 38 for receiving the
first tabs 58 of border 12b. As is shown in FIG. 2, panels 12 and
14 are joined at the intersection of border 12a with border 14a by
interengaging the first tabs 58 of border 12a with the first slots
38 of border 14a. Panels 12 and 16 are joined at the intersection
of border 12b with border 16b by interengaging the first tabs 58 of
border 12b with the first slots 38 of border 16b. With the
exception of the joint between panels 16 and 22, the remaining
joints of panels 12, 14, 16, 18, 20 and 22 of the sandwich panel
structure 10 illustrated in FIGS. 1 and 2 are joined at their
respective borders in a manner similar to the joint at the
intersection of borders 12a with 14a, and 12b with 16b, described
above. Panels 16 and 22 of sandwich panel structure 10 are joined
at their respective borders utilizing another joint configuration
illustrated in FIGS. 6 and 7 and described in detail below.
As used herein, the term slotted panel refers to any panel having
slots with respect to an adjacent tabbed panel to which it is
joined. That slotted panel may also be referred to as a tabbed
panel having tabs with respect to a slotted panel to which it is
joined. Likewise, the term tabbed panel refers to any panel having
tabs with respect to an adjacent slotted panel to which it is
joined. That tabbed panel may also be referred to as a slotted
panel having slots with respect to a tabbed panel to which it is
joined. Thus, in a sandwich panel structure of the present
invention, a single panel may be referred to as both a slotted
panel and a tabbed panel depending on the joint configuration
between adjacent panels. For example, following the foregoing
conforming definition, with respect to the joint configuration of
border 12a with border 14a, panel 12 is referred to as a tabbed
panel 42 while panel 14 is referred to as a slotted panel 24
according to the conforming definition of a tabbed panel 42 and a
slotted panel 24. Likewise, with respect to the joint configuration
of border 14b with border 16b, panel 14 is referred to as a tabbed
panel 42 while panel 16 is referred to as a slotted panel 24.
Accordingly, panels 12, 14, 16, 18, 20 and 22 are classifiable as
either a tabbed panel 42 or a slotted panel 24 depending upon the
joint configuration of panels 12, 14, 16, 18, 20 and 22 at the
intersection of their respective borders.
Turning now to FIGS. 3 and 5, illustrated is the arrangement of a
joint configuration of the sandwich panel structure 10 of FIG. 1.
FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 1
illustrating the arrangement of the joint configuration wherein a
first tabbed panel facesheet 50 of the tabbed panel 42 is engaged
with the slotted panel 24. FIG. 5 is an exploded perspective view
of the sandwich panel structure 10 taken from an interior
perspective of FIG. 1 illustrating the connective relationship of
the tabbed panel 42 with the slotted panel 24. In FIGS. 3 and 5,
the sandwich panel structure 10 is comprised of the slotted panel
24 fixedly connected to the tabbed panel 42. As can be seen in FIG.
3, the slotted panel 24 is disposed generally perpendicular to the
tabbed panel 42. However, the tabbed panel 42 may be disposed to
the slotted panel 24 at any angle. For example, the tabbed panel 42
may be disposed to the slotted panel 24 at an angle from about
45.degree. to about 135.degree.. The slotted panel 24 of the
present invention includes first slotted panel facesheet 34 and
slotted panel core body 26. The slotted panel core body 26 has
opposing first and second slotted panel sides 28, 30 and a slotted
panel end 32 which may be disposed perpendicular to the first and
second slotted panel sides 28, 30.
In FIG. 3, the slotted panel core body 26 is generally shown
constructed of cellular material arranged in a honeycomb
configuration, wherein the cellular material is also a heat
conducting material. The honeycomb material includes a plurality of
cells, the cells defining longitudinal axes extending perpendicular
to the first and second slotted panel side 28, 30. The engagement
of the first tabs 58 into the slotted panel core body 26 formed of
honeycomb material may aid in the conduction of heat away from the
interior of the sandwich panel structure 10. By arranging the
longitudinal axes of the honeycomb cells so that the axes extend
perpendicular to the slotted panel 24 with the first tabs 58
extending into the first slotted panel facesheet 34 parallel to the
longitudinal axes of the cells, the first tabs 58 provide an
efficient heat conduction path away from the interior of the
sandwich panel structure 10 to the exterior of the slotted panel
24. Although in FIG. 3 the slotted panel core body 26 is generally
shown constructed of cellular material arranged in a honeycomb
configuration, it is contemplated that the slotted panel core body
26 may be formed of any material and may be arranged within the
slotted panel core body 26 in any suitable manner.
FIGS. 3 and 5 further show the first slotted panel facesheet 34
disposed adjacent the first slotted panel side 28. The second
slotted panel facesheet 36 is disposed adjacent the second slotted
panel side 30. The first slotted panel facesheet 34 includes first
slots 38 passing therethrough. In accordance with the present
invention, the first and second tabbed panel and slotted panel
facesheets 34, 36, 50, 52 are formed of aluminum. However, it is
contemplated that the first and second tabbed panel and slotted
panel facesheets 34, 36, 50, 52 may be formed of any suitable
material.
As can be seen in FIGS. 3 and 5, the tabbed panel 42 includes a
tabbed panel core body 62 and the first tabbed panel facesheet 50,
the tabbed panel core body 62 having opposing first and second
tabbed panel sides 44, 46 and a tabbed panel end 48 which may be
disposed perpendicular to the first and second tabbed panel sides
44, 46. The first tabbed panel facesheet 50 is disposed adjacent
the first tabbed panel side 44. The second tabbed panel facesheet
52 is disposed adjacent the second tabbed panel side 46. The first
tabbed panel facesheet 50 also includes first tabs 58 disposed
along a first joint edge 54 as illustrated in FIG. 4.
Referring to FIG. 4, shown is a side view of a portion of the
tabbed panel 42 taken along line 4--4 of FIG. 3 illustrating the
arrangement of the first tabs 58 along the first joint edge 54 of
the tabbed panel 42. In FIG. 4, the first tabs 58 of the first
tabbed panel facesheet 50 are shown disposed along the first joint
edge 54. Each of the first tabs 58 is respectively sized and
configured to be received by a respective one of the first slots 38
upon insertion of the first tabs 58 into the first slots 38 for
joining the tabbed panel 42 to the slotted panel 24 at the first
joint edge 54. However, other shapes, sizes, configurations and
geometries for joining the first tabs 58 to the first slots 38 may
be utilized. For example, the first tabs 58 may be wave-shaped with
the first slots 38 configured accordingly to receive the first tabs
58.
Referring back to FIGS. 3 and 5, the first tabs 58 may be bonded to
the first slots 38. Optionally, the slotted panel core body 26 in
the area adjacent the first slots 38 may be filled with core body
filler in order to improve the bond of the first tabs 58 to the
tabbed panel core body 62 and increase the overall strength
characteristics of the joint. Also, the slotted panel end 32 may be
bonded to the second slotted panel facesheet 36. Further, the
slotted panel core body 26 adjacent the slotted panel end 32 may be
filled with core body filler in order to improve the strength
characteristics of the bond between the second tabbed panel
facesheet 52 and the slotted panel end 32. Still further, the
tabbed panel end 48 may be bonded to the first slotted panel
facesheet 34. The tabbed panel core body 62 adjacent the tabbed
panel end 48 may also be filled with core body filler in order to
improve the strength characteristics of the bond between the tabbed
panel end 48 and the first slotted panel facesheet 34. Although not
shown, an exterior flange may be bonded to the exterior of the
second slotted panel facesheet 36 and the exterior of the second
tabbed panel facesheet 52 in order to improve the strength
characteristics of the joint.
Referring still to FIGS. 3 and 5, the first tabs 58 of the first
tabbed panel facesheet 50 may be aligned to each other as shown.
However, other arrangements of the first tabs 58 may be utilized.
For example, configuring the first tabs 58 in a staggered formation
to be received by first slots 38 arranged in a complementary
formation may suffice. Additional arrangements are contemplated
regarding the engagement of the first tabs 58 with the first slots
38. For example, in FIG. 3, the first tabs 58 are shown extending
through at least about 50 percent of a thickness of the slotted
panel core body 26. However, it is contemplated that the first tabs
58 may be configured to extend through any range of thickness of
the slotted panel core body 26. For example, the first tabs 58 may
extend through at least about 80 percent of a thickness of the
slotted panel core body 26.
Turning now to FIGS. 6 and 7, illustrated is another joint
configuration of the sandwich panel structure 10. FIG. 6 is a
cross-sectional view taken along line 6--6 of FIG. 1 illustrating
the arrangement of the joint configuration wherein first and second
tabbed panel facesheets 50, 52 of the tabbed panel 42 are engaged
to the first slotted panel facesheet 34 of the slotted panel 24.
FIG. 7 is an exploded perspective view of the sandwich panel
structure 10 taken from an interior perspective of FIG. 1
illustrating the connective relationship of the first and second
tabbed panel facesheets 50, 52 of the tabbed panel 42 with the
first slotted panel facesheet 34 of the slotted panel 24. In FIG.
6, the first slotted panel facesheet 34 includes first slots 28 and
a plurality of second slots 40 formed therethrough and arranged in
two generally parallel rows. The tabbed panel 42 further includes
the second tabbed panel facesheet 52 disposed adjacent the second
tabbed panel side 46. The second tabbed panel facesheet 52 further
includes a plurality of second tabs 60 disposed respectively along
a second joint edge 56. Each of the second tabs 60 is respectively
sized and configured to be received by a respective one of the
first and second slots 38, 40 upon insertion of the second tabs 60
into the respective second slots 40 for joining the tabbed panel 42
to the slotted panel 24 at the second joint edge 56. As is shown in
FIG. 2, panels 16 and 22 are joined at their respective borders 16c
and 22a utilizing the joint configuration illustrated in FIGS. 6
and 7. Border 16c has first and second tabs 58, 60 extending
therefrom, with border 22a including first and second slots 38, 40
for receiving the first and second tabs 58, 60 of border 16c.
Panels 16 and 22 are joined by interengaging the first and second
tabs 58, 60 of border 16c with the first and second slots 38, 40 of
border 22a. It is recognized herein that there are an infinite
number of panel arrangements and border configurations that may be
assembled utilizing any combination of the joint configurations
illustrated in FIGS. 3 and. 6.
The sandwich panel structure 10 of the present invention differs
from existing sandwich panel structures in that the joint
configuration does not require additional joint members in order to
provide an efficient load path across the joint. The sandwich panel
structure 10 requires only treatment of at least one of first and
second tabbed panel facesheets 50, 52 of the tabbed panel 42 and
treatment of at least one of first and second slotted panel
facesheets 34, 36 of the slotted panel 24 to allow for the
interengagement of the tabbed panel 42 with the slotted panel 24 in
order to form a joint. Furthermore, the sandwich panel structure 10
of the present invention differs from existing sandwich panel
structures in that the sandwich panel structure 10 can assist in
the conduction of heat away from interior facesheets to exterior
facesheets. For example, spacecraft are often configured so that
the instrumentation, electronics and power systems are mounted on
interior facesheets such as those utilized in sandwich panel
structure 10. Although spacecraft typically include an active
cooling system for extracting the heat generated by the
instrumentation, electronics and power systems, the joint
configuration of the present invention can aid in the cooling due
to the engagement of the first tabs 58 of the tabbed panel 42 into
a slotted panel core body 26 of an adjacent slotted panel 24. It is
recognized herein that the joint configuration of the present
sandwich panel structure 10 may be utilized in any structure other
than the aerospace structure into which the present invention is
incorporated.
Additional modifications and improvements of the present invention
may also be apparent to those of ordinary skill in the art. For
example, in FIG. 7, second tabs 60 could be implemented using a
separate strip that is bonded to second tabbed panel facesheet 52.
Similarly, in FIG. 3, the extension of second tabbed panel
facesheet 52 that overlaps and may be bonded to slotted panel end
32 may also be a separate strip that is bonded to second tabbed
panel facesheet 52. Thus, the particular combination of parts
described and illustrated herein is intended to represent only
certain embodiments of the present invention, and is not intended
to serve as limitations of alternative devices within the spirit
and scope of the invention.
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